Snubbing device for the railroad car

ABSTRACT

This invention relates to the field of mechanical engineering, notably to snubbing devices with friction shock absorbers used in railroad car for freight cars. 
     The major tasks of proposed snubbing device for railroad car are the procurement of stable pressing of frictional wedge to inclined lateral surfaces of bogie bolster and to vertical surfaces of lateral frame of railroad car, and the procurement of friction force between vertical planes of friction wedge and lateral frame independently on car loading. 
     Proposed technical solution lets to increase security and improve the running gear.

This invention relates to the field of mechanical engineering, notably to snubbing devices with friction shock absorbers used in railroad car for freight cars.

It is known a snubbing device for railroad car that contains friction wedges that are pressed by the springs to the bogie bolster and to the lateral surfaces of the car frame. Each wedge has vertical surface that contacts with adjacent lateral surfaces of the car frame and inclined surface that contacts with inclined surface of the bogie bolster [1].

However above-mentioned device isn't effective for vertical shock absorption and has short service life because of heavy wearing due to high friction coefficient.

It is known a snubbing device for railroad car that contains spring group, bogie bolster, frictional wedge shock absorber [2].

Bogie bolster is made together with step-bearing, bearings for bearer and sockets for frictional wedges. It has the shape of bolster equal to flexural resistance and has closed box section. Spring group consists five, six or seven two-row springs, situated under the each end of bogie bolster, at the same time the extreme lateral springs of group support the wedges of shock absorber. There is a ring lug that come into the spring that support the wedge on the bottom bearing surface of wedge.

The wedges of absorber are situated in related sockets in bogie bolster, thrusted by its inclined surfaces in inclined surfaces of bogie bolster and pressed to bars on the lateral frames of car. The flexure of spring groups creates needed friction in shock absorbers. Lateral moves of bogie bolster are absorbed by the crosscut spring power of spring group. Wedge shock absorbers serves at the same time as a spring connection of bogie bolster with lateral frames of car.

Wedge shock absorbers that has friction power proportional to moves but with different dimension for descending and ascending movements is used for different railroad cars. Friction power in these absorbers arises at relative vertical and horizontal moves of rubbing wedges surfaces with frictional bars on the lateral frames of car. These wedge shock absorbers are able to absorb vertical and horizontal moves.

However one of the basic deficiencies of all frictional shock absorbers is the big static friction force that prevents the flexion of spring suspension when disturbing force is less than friction force of absorber.

The known constructions of snubbing devices don't provide the full process of vertical moves absorption that affects dynamics of railroad car movement and quality of its movement.

The closest technical embodiment to proposed technical embodiment is a snubbing device for railroad car that contains friction wedge shock absorber, bogie bolster placed over spring group, bogie bolster has the shape of isosceles trapezoid with big base over spring group in the section of place of installation of friction wedge shock absorber's wedges. At the same time the wedges of friction wedge shock absorber are placed with possibility of constant lateral frame of railroad car pressing by spring element to inclined lateral surfaces of bogie bolster and to vertical surfaces of lateral frame of railroad car, at the same time bogie bolster is made with bearing places for extreme springs of middle raw of spring group.

At the same time the angles of inclined lateral surfaces of friction wedge shock absorber and inclined lateral surfaces of bogie bolster that come into the contact and force of spring element shall be defined dependently on dimension of dynamic workload of car elements and whole railroad car.

Inclined lateral surfaces of friction wedge shock absorber and inclined lateral surfaces of bogie bolster, at their supposed prolongation situated in crossed planes [3].

Deficiencies of known snubbing device for railroad car are the absence of stable pressing of frictional wedge to inclined lateral surfaces of bogie bolster and to vertical surfaces of lateral frame of railroad car, and the absence of friction force between vertical planes of friction wedge and lateral frame.

The major tasks of proposed snubbing device for railroad car are the procurement of stable pressing of frictional wedge to inclined lateral surfaces of bogie bolster and to vertical surfaces of lateral frame of railroad car, and the procurement of friction force between vertical planes of friction wedge and lateral frame independently on car loading.

Result of proposed technical solution are reducing of dynamic percussive effects on the car and wagon elements in the process of usage, smoothness of movements, increasing of security, reducing of wearing and improvement of running gear.

The major task resolved with the help of coil (helical) springs posed in every internal cavity of wedges of friction wedge shock absorber and that are used as springing element and with the help of their pressing in by the bar that was additionally introduced.

Technical result is achieved by the fact that snubbing device for railroad car that contains friction wedge shock absorber, bogie bolster placed over spring group, bogie bolster has the shape of isosceles trapezoid with big base over spring group in the section of place of installation of friction wedge shock absorber's wedges. At the same time the wedges of friction wedge shock absorber are placed with possibility of constant lateral frame of railroad car pressing by spring element to inclined lateral surfaces of bogie bolster and to vertical surfaces of lateral frame of railroad car, the bogie bolster is made with bearing places for extreme springs of middle raw of spring group, at the same time coil springs function as springing element. These springs are posed in every internal cavity of wedges of friction wedge shock absorber and pressed in by the bar that was additionally introduced.

DESCRIPTION IN THE DRAWINGS

FIG. 1 represents proposed snubbing device assembled with biaxial railroad car.

FIG. 2 represents snubbing device with lateral frame of biaxial railroad car

Below we provide detailed description of invention with indication of positions.

Snubbing device for railroad car consists from friction wedge shock absorber 1, bogie bolster 2 and spring group 3.

Bogie bolster 2 has the shape of isosceles trapezoid with big base over spring group 3 in the section of place of installation of friction wedge shock absorber's 1 wedges 4.

At the same time the wedges 4 of friction wedge shock absorber 1 are placed with possibility of constant lateral frame of railroad car pressing by spring element to inclined lateral surfaces of bogie bolster 2 and to vertical surfaces of lateral frame 5 of railroad car.

Coil (helical) springs 6 posed in every internal cavity of wedges 4 of friction wedge shock absorber 1 are used as springing element and are pressed in by the bar 7 attached to the top plane of bogie bolster 2 by bolts 8.

Bogie bolster 2 is made with bearing places 9 for extreme springs of middle raw of spring group 3.

The angles of inclined surfaces of wedges 4 of friction wedge shock absorber 1 and lateral surfaces of bogie bolster 2 that come into the contact and force of spring element that is represented by coil (helical) springs 6 that press in the wedges 4, shall be defined dependently on dimension of dynamic workload on the car elements and whole railroad car.

Function of snubbing device for railroad car is perception of forces by spring group 3 at descending movement and absorption of fluctuations by friction force that appears in friction wedge shock absorber 1 at ascending movement.

Proposed construction of snubbing device for railroad car provides stable pressing in of wedges 4 to inclined lateral surfaces of bogie bolster 2 and to vertical surfaces of lateral frame 5 of railroad car, and provides stable friction force between vertical planes of friction wedges 4 and lateral frame independently on car loading.

At descendent movement snubbing device is working in the following order: bogie bolster 2 passes an effort to the springs of spring group 3 by compressing them. Friction wedge shock absorber 1 doesn't function at this moment. The wedges 4 of friction wedge shock absorber 1 move together with bogie bolster 2 pressed in it and in vertical planes of lateral frame 5 by spring element, which is coil (helical) springs 6, posed into internal cavity of every wedge 4 of friction wedge shock absorber 1 and pressed in by the bar 7 additionally introduced and attached to the top plane of bogie bolster 2.

At descendent movement the springs of spring group 3 release, the bogie bolster 2 goes up relatively lateral frame 5 of car. The wedges 4 of friction wedge shock absorber 1 pressed in by spring element, which represents the coil (helical) springs 6, posed into internal cavity of every wedge 4 unwedge between inclined lateral surfaces of bogie bolster 2 and vertical surfaces of lateral frame 5 of railroad car. Absorption of movements in friction wedge shock absorber 1 at ascending movement functions due to appearance of friction force between vertical planes of wedges 4 of friction wedge shock absorber 1 and lateral frame 5 of car.

The effectiveness of movements absorption process provided due to constructive modification of disposition of wedges 4 of friction wedge shock absorber 1, and introducing of spring element which is represented by the coil (helical) springs 6, posed into internal cavity of every wedge 4 and that provides functional connection between all mentioned elements of construction. At the same time it appears the stable force of pressing in of wedges 4 to inclined lateral surfaces of bogie bolster 2 and to vertical surfaces of lateral frame 5 of railroad car, and condition of presence of stable friction force between vertical planes of friction wedges 4 and lateral frame independently on car loading.

Proposed construction of snubbing device for railroad car lets to spring group 3 maximally perceive the forces that appear at descending movement and effectively absorb the movements at ascending movement due to appearance of friction force in friction wedge shock absorber 1.

Constructive solution of proposed snubbing device let to change the direction of friction force that appears between surfaces of wedges 4 and lateral frame 5 of car on opposite direction, that means maximally absorb the fluctuations at ascending movement and reduce dynamic percussive effects on the car and wagon elements and smoothness of movements.

Proposed technical solution lets to increase security and improve the running gear.

Sources of Information

-   1. U.S. Pat. No. 6,269,752, MΠκ⁷ B61F5/12 -   2. Book. Railroad Cars. Edited by L. A. Shadura, published by     “Transport”, Moscow, p. 166-170, p. 185-190, (prototype). -   3. Patent of Russian Federation N^(o) 2259292, MΠκ⁷ B61 F5/12     (prototype) 

1. Snubbing device for railroad car that contains friction wedge shock absorber, bogie bolster placed over spring group, bogie bolster has the shape of isosceles trapezoid with big base over spring group in the section of place of installation of friction wedge shock absorber's wedges. At the same time the wedges of friction wedge shock absorber are placed with possibility of constant lateral frame of railroad car pressing by spring element to inclined lateral surfaces of bogie bolster and to vertical surfaces of lateral frame of railroad car, at the same time bogie bolster is made with bearing places for extreme springs of middle raw of spring group. This device differs from another one due to spring element, which represents the coil (helical) springs 6, posed into internal cavity of every wedge of friction wedge shock absorber and pressed in by the bar additionally introduced and attached to the top plane of bogie bolster. 